Based on the information in the graph, in which month do 24% of the students have a birthday?

Direct mail advertisers send solicitations ("junk mail") to thousands of potential customers in the hope that some will buy the

harina [27]

Answer:

The interval is (.0817, .118).

Step-by-step explanation:

Let's make this interval! The easy way is to go to STAT->TEST->A, 1-prop z-int, but I will show the long way.

1. Conditions

First we must check the conditions.

Randomization condition: The sample is given to be random, so we can assume independence.

Success/failure condition: Both np>10 and nq>10 must be met.

np = 1030(103/1030) = 103 ✓
nq = 1030(927/1030) = 927 ✓

10% condition: The sample cannot be greater than 10% of the population.

10n < N, 10(1030) < 200000 ✓

All conditions are met, so we can use a 1-proportion z-interval to represent the data.

2. Mechanics

Find $\hat{p}$ , the sample proportion.

103/1030 = .1

$\hat{q}$ , then, the probability of not p, is 1 - .1 = .9

Find z* (z star), the critical z-value.

You can do this on your calculator using 2nd->VARS->3 (or you can memorize it - it's 1.96. Winky face.) This is called the invNorm function, that takes the left side area under the normal curve. But what do we plug in to the invNorm function?

invNorm(.975) = 1.96

Plug values into the equation.

$\hat{p}$ ± z* $\sqrt{\frac{\hat{p}\hat{q}}{n} }$

.1 ± 1.96 $\sqrt{\frac{.1*.9}{1030} }$

.1 ± 1.96(.00935)

.1 - .0183 = .0817

.1 + .0183 = .118

(.0817, .118)

3. Conclusion

Based on this sample, we are 95% confident that the proportion of people the company contacts who may buy something is between .0817 and .118. That isn't very likely, but maybe they'll make a little profit!

5 0

3 years ago

Round to 2 decimal places *

EleoNora [17]

Answer: The circumference of the dome is therefore 149.15 feet or 47.5π feet

Step-by-step explanation:

A scale is basically referred to as the ratio of the dimensions of an object as represented in a draft to the real or true dimensions of the object being drafted.

The figure(s) on the left of the ratio sign represents the size and dimensions of the model with respect to the actual size or dimensions of the object. On the other hand, the figure on the right hand size represents the actual dimensions and size of the real object.

So, if an object is being drawn with the ratio, 1cm : 5cm it means that the size of the object is being reduced because every 5cm of the actual object will always be represented by 1cm in the drawing. If the object is being drawn with a scale of 5cm : 1cm then the actual size of the object will be increased in the drawing. That is, for every 1cm in the actual dimensions of the object, there will be a 5cm representation in the drawing.

Now, the architect draws with a scale of 0.25 inches : 1 foot. If the diameter of the hemispherical dome is 23.75 inches in the scale model, then the actual diameter of the dome is:

0.25 inches ------- 1 foot

23.75 inches ------- ? feet

= 23.75/0.25 × 1

= 95 feet

Therefore, the actual diameter of the dome is 95 feet. We are now required to find the circumference of this dome.

The dome is a hemisphere which literally means half of a sphere. So, if the formula for finding the circumference of a sphere is πd, that of a hemisphere will then be πd/2. Since the diameter is already known to be 95 feet, the circumference of the hemisphere =

(π × 95)/2

=47.5π feet

Or

If π = 3.14, then the circumference = (3.14 × 95)/2 = 149.15 feet

The circumference of the dome is 149.15 feet or 47.5π feet

5 0

3 years ago

In ΔJKL, j = 93 cm, k = 82 cm and l=86 cm. Find the measure of ∠J to the nearest degree.

zhuklara [117]

Answer:

5

Step-by-step explanation:

Answer:

85t

Step-by-step explanation:

1. Volume of a cone: 1. V = (1/3)πr2h 2. Slant height of a cone: 1. s = √(r2 + h2) 3. Lateral surface area of a cone: 1. L = πrs = πr√(r2 + h2) 4. Base surface area of a cone (a circle): 1. B = πr2 5. Total surface area of a cone: 1. A = L + B = πrs + πr2 = πr(s + r) = πr(r + √(r2 + h2))

hope this helps

8 0

2 years ago

Read 2 more answers

What is the y intercept of f(x)=4 - 5x?

vovangra [49]

The point is on (0,4)

5 0

3 years ago

2/5 of a Number is what percentage of that number HELP

Nata [24]

Answer: 40%